Abstract: Ferric magnetic graphene oxide was prepared using hydrothermal precipitation method，and immobilized pectinase on it with crosslinking regeant. There is few report on the immobilisation of pectinase on magnetic graphene oxide (MGO). Active groups and characteristics were characterized using FT-IR and SEM analysis. It was illustrated that active groups (—OH etc.) were formed on MGO，which lead to well dispersion in water phase. High loading densities (1453mg per g of support) was obtained，which is higher than that of activated carbon and diatomite. In addition，kinetic parameters of enzymatic catalysis were investigated，and characterized by Kcat 7.41h?1，catalytic efficiency (Kcat/Km) 0.98mL/(h?mg) and Km 7.55mg/mL. Stability of immobilized enzyme was enhanced and 58% residual activity was maintained after 10 cycle of application.

Key words: magnetic graphene oxide, immobilisation of enzyme, pectinase, kinetic parameters of enzymatic catalysis, recover and reuse

摘要： 磁性氧化石墨烯固定化酶的研究鲜见报道，本实验采用水热沉淀法制备了铁磁性氧化石墨烯（magnetic graphene oxide，MGO），通过交联剂固定化果胶酶。采用红外光谱和SEM表征了制备的MGO的活性基团和特性。结果表明MGO具有—OH等亲水活性基团，可以较好地分散在水相催化体系中。磁性氧化石墨烯的蛋白上载量可达1453mg/g MGO，远高于颗粒活性碳，硅藻土和粉末活性炭的上载量。并且研究了酶催化的动力学，酶的催化转化值7.41h?1，催化效率0.98mL/(h?mg)，Km7.55mg/mL。固定化酶稳定性明显增强，且重复使用10次活性仍然可以保持在初始酶活的58％。

关键词: 磁性氧化石墨烯, 固定化酶, 果胶酶, 酶催化动力学, 回收利用